Separation of multiple signals from their superposition recorded at several sensors is an important problem that shows up in a variety of applications such as communications, biomedical and speech processing. The separation task is made difficult by the fact that very little is known about the transmission channel or the input signals and thus the separation is commonly referred to as blind.
In L. Zhang and A. Cichocki, “Blind Deconvolution of Dynamical Systems: A State Space Approach’, Journal of Signal Processing, vol. 4, No. 2, Mar. 2000, pp. 111-130 a controller canonical parametrization of the mixing system is described.
In Ober, “Balanced Parametrisation of Classes of Linear Systems” SIAM Journal Control and Optimisation, Vol 29, pp 1251-1287, 1991” there is described a method of Balanced Parametrisation exclusively within the continuous-time domain.
The above prior art does not provide for a balanced parametrization that avoids problems of pre-estimation of the order of the mixing system, instability of the mixing system due to pole-zero cancellation and estimation of a balanced parametrization of the mixing system in the discrete-time domain.
In this specification, including the claims, the terms ‘comprises’, ‘comprising’ or similar terms are intended to mean a non-exclusive inclusion, such that a method or apparatus that comprises a list of elements does not include those elements solely, but may well include other elements not listed.